I created a new MVC project, and test the remote validation in the about page.

1)Controller Home:

               public ActionResult ValidateTestName(string testName)
        {
            return Json(!testName.Equals("test"),
                        JsonRequestBehavior.AllowGet);
        }

2)Model:

using System.ComponentModel.DataAnnotations;
using System.Web.Mvc;

namespace MvcApplication1.Models
{
    public class AboutModel
    {
        [Required]
        [Remote("ValidateTestName", "Home", ErrorMessage = "this Name already be used.")]
        public string TestName { get; set; }

        [Required]
        [Range(20, 44)]
        public int Age { get; set; }
    
    }
}  

3)View:
In _Layout.cshtml:

In About.cshtml

@model MvcApplication1.Models.AboutModel
@{
    ViewBag.Title = "About Us";
}

About

     Put content here.
     @using (Html.BeginForm())
     {
         @Html.EditorForModel();
                               
        "submit" value="Submit" />                      
     }

It is working perfect under FireFox 6:

but not working in my IE9 :(...
I have downloaded Jquery.Validation 1.8.1 try to fix this issue, but looks still unlucky.
(Jquery.Validation site : http://bassistance.de/jquery-plugins/jquery-plugin-validation/)


but this post in stack overflow said it tested in Chrome 10.0, IE9 and FireFox 4.0